Move most code into src/Oracles/ submodules.
Move most code into src/Oracles/ submodules.

bgamari/shaking-up-ghc,sdiehl/ghc,snowleopard/shaking-up-ghc,quchen/shaking-up-ghc,izgzhen/hadrian,sdiehl/ghc,sdiehl/ghc,sdiehl/ghc,sdiehl/ghc,sdiehl/ghc,snowleopard/hadrian,sdiehl/ghc